Portuguese explorer Prince Henry, known as the Navigator, was the first European to methodically explore Africa and the oceanic route to the Indies. From his residence in the Algarve region of southern Portugal, he directed successive expeditions to circumnavigate Africa and reach India. In 1420, Henry sent an expedition to secure the uninhabited but strategic island of Madeira.

In 1425, he tried to secure the Canary Islands as well, but these were already under firm Castilian control. In 1431, In 1344, Pope Clement VI named French admiral Luis de la Cerda Prince of Fortune and sent him to conquer the Canaries. In 1402, Jean de Bethencourt and Gadifer de la Salle sailed to conquer the Canary Islands but found them already plundered by the Castilians. Although they did conquer the isles, Bethencourt's nephew was forced to cede them to Castile in 1418.

In 1455 and 1456 two Italian explorers, Alvise Cadamosto from Venice and Antoniotto Usodimare from Genoa, together with an unnamed Portuguese captain working for Prince Henry of Portugal, followed the Gambia river, visiting the land of Senegal, while another Italian sailor from Genoa, Antonio de Noli, also on behalf of Prince Henry, explored the Bijagós islands, and, together with the Portuguese Diogo Gomes, the Cape Verde archipelago.

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